A bus system in which data are transferred as messages under the ISO 11898:1-2015 standard constituting the CAN protocol specification, using CAN FD, is often used for communication between sensors and control devices, for example in vehicles. The messages are transferred between the bus subscribers of the bus system, e.g., a sensor, control device, transducer, etc.
German Patent Application No. DE 10 2012 209 093 A1 describes a subscriber station of a bus system which is capable, in the context of an error in a CAN bus communication, of aborting a message at an arbitrary abortion point. The message must then be transmitted again, which increases bus occupancy.
As the number of functions of a technical system or a vehicle rises, the data traffic in the bus system also increases. In addition, it is often required that the data be transferred from the transmitter to the receiver more quickly than before. A consequence of this is that the required bandwidth of the bus system will increase even further.
In order to allow data to be transferred at a higher bit rate than with CAN, an option for switching over to a higher bit rate within a message was created in the CAN FD message format. With such techniques, the maximum possible data rate is increased beyond a value of 1 Mbit/sec by using a faster cycle time in the region of the data fields. Such messages are also referred to hereinafter as “CAN FD frames” or “CAN FD messages.” With CAN FD, the payload data length is extended from eight to as many as 64 bytes, and data transfer rates are appreciably higher than with CAN.
Although a CAN- or CAN FD-based communication network offers a very large number of advantages, for example with regard to its robustness, its speed is nevertheless much lower as compared with a data transfer in, for example, 100 BASE-T1 Ethernet. In addition, the payload data length of up to 64 bytes which has hitherto been reached with CAN FD is too short for some applications.